Protection for looms



Feb. 19, 1952 D. w. HOWE, JR., ET AL PROTECTION FOR LOOMS 3 Sheets-Sheet1 Filed March 12, 1949 INVENTORS, DONALD W. HOWE JR.

VICTOR F. SEPAVICH 62. R M

ATTORNEY.

Feb. 19,1952 D. w. HOWE, JR., ET AL 2,586,335

PROTECTION FOR LOOMS Filed March 12. 1949 3 Sheets-Sheet 2 7| FIG.8

MN is IO] 76 FIG.? @751 FIG.2 INVENTORS DONALD w. HOWE JR.

VICTOR F. SEPAVIVGH ATTORNEY Feb. 19, 1952 D. w. HOWE, JR, ET AL 2, ,3 5

I PROTECTION FOR LOOMS Filed March 12, 1949 5 Sheets -Sheet 3 FIGJZINVENTORS DONALD W. HOWE JR.v VICTOR F. SEPAVIGH m uo FIGJO L i ATTORNEYPatented Feb. 19, 1952 PROTECTION FOR LOOMS Donald W. Howe, Jr., Ware,and Victor F. Sepavich, Worcester, Mass., assignors to Crompton &Knowles Loom Works, Worcester, Mass, a corporation of MassachusettsApplication March 12, 1949, Serial No. 81,164

This invention relates to improvements in electric protection means tostop a loom if the shuttle while in flight fails to reach a given pointalong the lay at a given time in the loom cycle due to the fact that theshuttle is not running properly.

Loom lays are customarily provided with a protector rod having securedto it daggers normally positioned to engage bunters at least one ofwhich is connected to the loom stopping mechanism. The protector rod hasfingers which engage the shuttle binders and if the shuttle is runningproperly it enters a shuttle box in time to rock the protector rod anddepress the daggers before they can engage the hunters. If the shuttlefails to enter the shuttle box on time the daggers remain in stoppingposition and strike the bunters to efiect stoppage of the loom. Suchmechanisms act to stop the lay very abruptly and are likely to breaksome part of the loom. Stopping of the loom is necessarily abrupt due tothe short time elapsing between proper boxing of the shuttle and thepoint in the loom cycle where a shuttle in the shed would break thewarp.

It is an important object of the present invention to provide means bywhich proper running of the shuttle can be determined before it reachesthe shuttle box, thereby allowing more time for stop-ping of the loom.This means may include two parts which due to relative motion cooperateto produce an electric change in at least one of them. One of theseparts is on the lay and the' other is on the shuttle, and when theshuttle is running correctly the two parts cooperate to generate anelectric impulse which is utilized to cause energization of an electriccircuit at a given time in the loom cycle which will permit continuedloom operation. If the shuttle is running slow, however, the impulsewill be generated after said given time andtoo late to effectenergization of the electric circuit at the required time, and loomcontrolling means will stop the loom. The part'on the lay may take theform of a coil surrounding a permanent magnet and the part on theshuttle may be a body of metal which when passing over the coil willalter the magnetic field in such a manner as to inducej'an electricpotential or impulse in the coil. The energy for developing thispotential or impulse is derived from the shuttle, or more properly, thepicking mechanism which propels 26 Claims. (-Cl. 139-341) two coilsspaced along its length and located on opposite sides of thelongitudinal center of the lay. When two coils are used a single flightof the shuttle will generate two electric impulses the first of whichoccurs too early to affect the loom controlling means, but the secondimpulse derived from the other coil will normally occur at a time whenthe loom controlling means would stop the loom unless prevented fromdoing so.

The generated impulse controls the grid of an electronic tube in circuitwith a stopping means controlling electromagnetic device. Normally thelatter will be deenergized at the aforesaid given time in the loom cycledue to the normal electric condition of the grid. When the impulseoccurs it changes the electric condition of the grid so that electriccurrent can flow through the tube to energize the electromagneticdevice. If the impulse occurs on time the loom controlling means, whichmay be either electric or mechanical, will be prevented from stoppingthe loom, but if the impulse is generated too late, or is not generateddue to stoppage of the shuttle in the warp shed, the electromagneticdevice will not be energized by the time the stopping means normallyacts, and the loom will be stopped.

With this general object in view, and other objects which will appear asthe description proceeds, the invention resides in the combination andarrangements of parts hereinafter described and claimed.

In the accompanying drawings, wherein three forms of the invention areset forth,

Fig. 1 is a front elevation of a loom having the preferred form of theinvention applied thereto,

Fig. 2 is an enlarged detailed side elevation looking in the directionof arrow 2, Fig. 1, the cover of the loom driven switch being removed,

Fig. 3 is a vertical section on a reduced scale on line 3--3, Fig. 2,

Fig. 4 is a front elevation of a shuttle used with the invention,

Fig. 5 is a plan view of the shuttle shown in Fig. 4,

Fig. 6 is an enlarged transverse vertical section on line 66, Fig. 4,

Fig. 7 is a diagrammatic view showing a form of electric circuit whichcan be used with the preferred form of the invention,

Fig. 8 is a view similar to Fig. 7, but showing a circuit which can beutilized with the first modified form of the invention,

Fig. 9 is a side elevation of part of a loom showing the lever mechanismand solenoid used in the first modified form of the invention,

Fig. 10 is a horizontal section on line Iii-10, Fig. 9, showing theparts in normal position,

Fig. 11 is similar to Fig. 10, but snowing the parts in the positionsthey occupy when the shuttle is running properly,

Fig. 12 is a vertical section on line l2--l2, Fig. 9,

Fig. 13 is an enlarged plan of part of the lay and one of the coils,looking in the direction of arrow 13, Fig. 1,

Fig. 14 is a vertical section on line l4-|4, Fig. 13. and

Fig. 15 is a diagrammatic plan for aloom lay showing the secondmodincation of the invention in which only one coil on the lay is used.

Relerring particularly to Fig. l, loom frame I is provided with a lay l6which swings backwardly and forwardly during loom operation. The loomhas a top shaft ll provided with gears I8 meshing with gears IS on thebottom shaft 2i]. The lay is provided with right and left gangs, R andL, respectively, of shuttle boxes which are shifted relatively to thelay by known mechanism not shown but operated by a head mechanismdesignated as Right and left picker sticks 2i and 22, respectively, areeach operated by picking mechanism including a cam 23. Sleeves 24 and 25slidable on but rotating with the bottom shalt are provided with pickingrolls 28 and 21, respectively. The sleeves are operatively connected tolevers 28 which are connected by a rod 2s, and a positioning rod 30operated by mechanism K moves the sleeves lengthwise of shaft 2i] sothat only one picking roll 26 or 21 at a time will be able to engage acam 23.

During loom operation the picker sticks will be given operative pickingmotions determined by the positions of the sleeves 24 and 25. The loomshown in Fig. l is of the pick and pick type employing three shuttlesSI, S2 and S3. Whenever a picker stick operates it will propel one ofthe shuttles from the associated shuttle box gang across the lay l6toward the other shuttle box gang. The warp shed of the loom willgenerally occupy some such space as that indicated at W in Fig. 1.

The loom is driven by a motor M which has a pinion 3| meshing with amotor gear 32 secured to the topshaft H. Whenever the motor is runningthe loom will be in operation, and whenever the motor is stopped, aswill be set forth more particularly hereinafter, the loom will bestopped.

The matter thus far described sets forth a type of loom on which theinvention can be used, but it is to be understod that the invention isnot limited in its use to this particular type of loom.

In carrying the invention into effect means are provided by which theshuttle gives an electrical indication when it arrives at a given pointalong the length of the lay between the shuttle boxes R and L. If theshuttle is running properly the indication will be given in time toprevent loom stoppage, but if the shuttle is running slow the indicationwill be given too late to prevent loom stoppage. The shuttles are allequipped with means which assist in giving the indication, and adescription for one of them will suffice.

As shown in Fig. 4, where shuttle SI is set forth, the shuttle has abobbin compartment 35 containing a weft carrier, such as a bobbin 36.The shuttle body is made of non-magnetic material, such as wood, and hasfront and back walls 31 and 38 and a floor or bottom39. Mounted on theunderside of the shuttle is an elongated metallic plate 40 extendinglengthwise of the shuttle. This plate is below the bobbin 36 and closeto the bottom surface of the shuttle but spaced slightly thereabove, asshown at M, Fig. 6. This plate which is held in place either bycementing or by a close fit. or in any other convenient manner, islocated preferably centrally of the length of the shuttle as indicatedin Fig. 5 and is made of a magnetizable substance or material which willconduct magnetic lines of force. For this purpose the plate may be madeof ferrous metal, such soft steel or iron. As shown herein the platewill normally be demagnetized, but it is within the spirit of theinvention to have plate 40a permanent magnet if desired. Onlyone plate40 located centrally of the shuttle is shown, but the invention is notlimited to a single plate thus placed.

The lay includes a laybeam 42, which may be made of wood, to the top ofwhich a race plate 43 is secured. The race plate may be made of wood ormetal, preferably steel, and extendsbetween theshuttle boxes at each endof the lay. The lay has mounted thereon between the shuttle gangs R andG two spaced electric induction units El and E2, preferably but notnecessarily under the warp shed. Both of these units are alike and madeas shown in Figs. 13 and 14, wherein unit E2 is shown in detail. Theunits El and E2 are preferably equally spaced from their correspondingshuttle box gangs.

The unit E2 includes a permanent magnet 44 having poles 45 and 46 and acoil of wire 41 which is wound around the magnet. Magnet 44 is securedto a support 48 made of non-magnetic material, such as a plastic, andhas its poles slightly below the top 49 of the race plate, see Fig. 14.The race plate has'a-slot 50 therein into which the upper part 5| of thesupport fits. The top surface 52 of the part 5| is preferably alignedwith the top surface of the race plate to form a substantiallycontinuous top surface for the lay. Slot 50 is large enough so that nopart of the race plate is near the poles of the magnet, see Fig. 13,hence if the race plate is made of steel it will not be close enough tothe magnet to provide a path for the magnetic lines of force of thepoles. Support 48 is secured as at 53 to the lay beam. The center tocenter distance between poles 45 and-46 is substantially equal to thelength of plate 40, although this is not an essential relation. Thepoles 45 and 48 are also spaced fromthe-reed 54 which is usually made offlat sheet'steel dents.

The coils of the two units El and E2 may be connected as showndiagrammatically in Fig. 7; a side of each coil being connected to awire 55 and the other side of each coil being connected to a singlewave'rectifier. As shown in Fig. 7, rectifiers 5t and 5'! are providedfor coils El and E2, respectively. These rectifiers are so arranged thatthey permit only positive electric current to flow from the coils to awire 58 which is connected to both rectifiers.

As shown in Fig. 7 the electric-circuit used with the preferred form ofthe invention includes an electronic power tube 60 having a plate 6|, acathode 62, and a control grid 63. The latter is connected through aprotective resistance R! to wire 58.

Wire 55 is connected to a wire grounded at 56, and a small condenser Cland a second resistance R2 are connected in parallel across wires 58 and65 on that side of. resistance RI opposite to the tube 88. One side of apreferably variable resistance R3 is connected to wire 85, while itsother side is connected to cathode 62 by wire 61. A wire 68 connectswire 61 to one side of a resistance R4 the other side of which isconnected by Wire 69 to a secondary ll! of a transfermer T. Thesecondary supplies relatively high voltage alternating current and isconnected to wire 65, and tends normally to cause electric current toflow through tube 60. Resistance R4 is considerably higher thanresistance R3, and the cathode is kept at a voltage slightly aboveground.

Plate 6l is connected by wire H to a normally deenergized relay l2controlling a switch 13 having a blade or contactor l4 and a stationarycontact l5. Relay 12 is also connected to wire 69 and is in parallelwith a relatively large electric condenser C2. Switch 13 is connected bywires 16 and l! to a motor control unit MC not shown in detail butindicated dia rammatically in Fig. 7.

A rotary switch cam 30 has a relatively long dwell 8| and a. short campoint 82 for operation of blade 83 of a switch 84 having a stationarycontact 85. Blade 83 is connected to wire l6,

while contact 85 is connected to wire 1?, so that N switches l3 and 84are parallel and each is able to control the electrical apparatus withinthe motor controller MC. One or the other of these switches must beclosed to enable the controller MC to maintain motor M in operation. Cam8!] one or the other of the controlling unit El or E2, depending uponthe direction of travel.

The cam 80 and switch 84 may be arranged as shown in Fig. 2, wherein thetop or crank shaft H, which may be considered a member moving regularlyduring loom operation, is shown as having keyed thereto a sprocket wheel86 around which is trained a chain 8?. The chain is trained around asecond sprocket wheel 88 secured to a stub shaft 89, see Fig. 3, towhich cam 88 is secured. Wheels 86 and 88 are th same size, hence cam 80turns in unison with the top shaft ll.

Shaft 89 turns in two aligned bushings 90 driven into the shell 9| of anadjusting member 92. A set screw 93 holds the angular setting of member92 relatively to a stand 94 fixed to the loom frame. A disk 85 ofinsulation material is fastened within the enlarged cup 86 of member 92and supports an arcuate contact plate 91, see Fig. 2, held to the diskin angularly adjusted position by screws 98 passing through slots 99 inplate 9'! and tapped into the disk. The previously described contact 85is carried by the contact plate 91, and switch blade 83 is also mountedon disk 95. Wire I00 connects contact 85 to wire 11, and wire l0lconnects the switch blade 83 to wire 16.

Set screw 93 permits angular adjustment of switch 84 with respect to thecam 80 to vary the time of opening of the switch with respect to theloom cycle. The structure shown at the right of Fig. 2, and in Fig. 3,is given merely as an example of a circularly adjustable switch the timeof opening of which can be adjusted relatively to the loom cycle.

During loom operation switch 84 will be closed for the greater part ofeach one pick cycle of the loom, but will be opened by cam point 82 whenthe metallic plate on the running shuttle should pass over one or theother of the induction units El and E2 depending upon the direction ofmotion of the shuttle. Opening of switch 84 would normally cause themotor control MC to stop the motor M, but if switch 13 is closed at thistime control MC will remain in normal condition and the motor willcontinue to run and drive the loom. If, on the other hand, switch 13 isnot closed at this time control MC stops the motor.

Assuming that the shuttle has been picked from gang R by the pickingmechanism at the right end of the loom and is moving to the left it willpass over the induction unit El while switch 84 is still closed due tothe dwell Bl of cam and the electric potential developed in unit El willr change grid 63 so that current can flow through the tube, but thiswill have no effect, since switch 84 is closed at this time. As theshuttle continues to move it will pass over the second induction unit E2and will generate a single cycle of alternating current in the coil. Itwill be noted that the picking mechanism supplies the energy necessaryto generate the electric potential or impulse in the units El and E2.The rectifier 51 will block out the negative alternation of this cyclebut will permit the positive alternation to be impressed on the grid 63through the resistance RI and at the same time will charge the smallcondenser Cl. As soon as the shuttle has passed the unit E2 thecondenser Cl will start to discharge through resistance R2 and in doingso will hold the grid 63 in the positive condition relatively to thecathode 62. The grid will be held at this potential lon enough so thatcurrent can pass through the electronic'tube 60, whereupon the secondary10 will be able not only to energize the relay 12 but also chargecondenser CZ which is larger than condenser Cl. When the potential ofthe plate Gl changes from positive to negative the condenser C2 willdischarge through the relay l2 and in this way the latter can be keptenergized for a period corresponding to the period of opening of switch84. If the shuttle is running on time relay 12 will close switch 13during the time that switch 84 is open, and there will be no change inthe control MC, and the loom will continue to run.

If the shuttle is runnin late and does not pass over unit E2 until afterswitch 84 is open, then both switches 13 and 84 will momentarily be openand the circuit through wires 18 and 71 will be open and control MC willcause stoppage of motor M. This stoppage may be efiected by any of thecommercial devices which are available for this purpose, these devicesof themselves forming no part of the present invention. The control MCmay if desired include electrical apparatus for plugging the alternatingcurrent motor M with direct current.

On return of the shuttle to the right, Fig. 1, the same conditions willexist as those already described, except that the controlling electricpotential will be generated in induction unit El. If the shuttle is ontime relay '12 will close switch 13 as before and the loom will continuein operation.

The adjustment of switch 34 relative to the cam member 80 will permitsome variation in the time of opening of switch 84 by cam point 82 withrespect to the loom cycle so that adjustments may be made to compensatefor diiierent shuttle speeds for which the picking mechanism may be set.

When two coils are used as set forth in Fig. 7 the rectifiers 56 and 5!will not only act to block out the negative alternations generated inthe 7], unitsc-EI and E2,.but.wil1 also prevent each unit fromdischarging through. the other unit and the full energy developed ineach unit can therefore-.bentilized for the grid and charging ofcondenserCI.

In the first modified form of the invention the electric switch 84 andcam 80 are dispensed'with and in their place is used a mechanicallyoperating device which tends normally to stop the loom at: a given pointin the loom cycle, as is customary in protection devices, but themechanism'zwill be prevented from effecting loom stoppage ;if theshuttle is on time and generates an electric potential .at the correctpoint in the loom cycle;

Referrin to Fig. 9, the top shaft I! of the loom has secured thereto acam III] having a point III which periodically rocks an actuator leverI121 The latter is pivoted on a stud II3 fixed onaa" stand II4 held instationary position on the loom frame. The upper part of lever H2has.:an arm H5 which as viewed in Fig. 9 has a periodically recurringmovement to the right which occurs at the time in each one pick cycle ofthe loom when the shuttle should pass over the induction unit which isrelied upon for controlling the grid of tube 60.

A knock-off or stopping lever I also pivoted on'stud I'l3"has the upperend thereof operatively connected by a rod I2I to the piston I22 of ahydraulic cylinder I23 which is appropriately connected to a hydraulicbrake I24 for the loom. Mounted on lever I20 is an element shown as aplunger I25, seeFig. 10, slidable on the lever and normally in the pathof lever arm I15. plunger is, operatively connected to a small lever I26moving about a pivot I2'I fixed with respect to lever I20. A solenoidI28 also mounted on lever I20 has a core I29 connected as at I30 tolever I26. A compression spring I3! interposed between the solenoid andlever I26 holds the latter normally in the position shown in Fig. 10with the element or plunger I25 in stopping position in front of leverarm I I5. When the solenoid I23 is energized the plunger I25 is movedout of thepath of lever arm II5 and the latter has an idle motion. If,on the other hand, the plunger l25'is still in the path of lever arm iI5when the latter has its periodic rocking, which occurs every pick of theloom, then hydraulic pressures are developed within the cylinder I23 andthe loom is stopped by brake I24. Cam H0, lever arm 5', plunger I25, andlever I20 and parts operated by it are loom controlling means tending atregularly "recurring one pick intervals to stop the loom.-

The circuit for controlling the solenoid i213 may be substantiall thesame as that already described for the preferred form of the inventionexcept for slight modifications. This circuit, shown in Fig. 8, issimilar to the greater part of the circuit shown in Fig. '7. Thesolenoid I28 takestheplace of the relay I2, and electric condenser C3,having preferably a somewhat larger capacity than C2, is in parallelwith the solenoid.

From the description already given it i believed that the operation ofthe modified form will be understood. Lever arm Iit will rock at thetime the shuttle-should pass over the controlling induction unit El orE2, and if the shuttle is on time it will induce a potential which willchange the electric condition of grid 53 to permit current to flowthrough the tube and solenoid I28 and cause the latter to move theplunger I25 out of the path of lever arm H5 just before the This 1latter'starts on aworkingpstroke. At the same time the condenser C3 willbe-charged to keepthe solenoid I28 in a continued state of energizationfor a short interval after the tube-ceases to fire. One purpose for thiscontinued energization is to prevent spring I3I from forcing the end ofplunger I25 against the lever arm I I5 and thereby avoid wear. It isunderstood of course that the essential function of the electric circuitwill have been performed if the shuttle is on time and plunger I25 hasbeen moved to a non-stopping position, such as shown in Fig. 11, justbefore cam point III rocks lever lI2.

While solenoid I28 has been shown as being directly energized by currentflowing through the tube 60 it will be within the spirit of theinvention if the solenoid is replaced by a relay similar to relay "I2and a switch controlled by thisrelay will close a circuit through thesolenoid. This will introduce an additional electrical step which mayinvolve a slight additional time delay between the passage of theshuttle over one or the other of the units El or E2 and removal ofplunger I25 from the path of lever arm H5, but an adjustment can be madein the setting of cam IIB to take account of this very slight delay. CamH0 is adjustable angularly on shaft II by means of set screw I30, hencethe time of rock ing of lever II2 can be varied relatively to the loomcycle.

In the second modification of the invention a single unit E3 is locatedon the lay midway between the shuttle box gangs, or the ends of the raceplate. When a single unit is used as shown in Fig. 15 the switch 84 willbe adjusted relatively to the cam to open earlier in the loom cycle thanis the case when two units are used. Also, an adjustment of cam 0 willbe necessary to rock lever arm II5 earlier. From this it will be seenthat the single coil E3 can be used with either the preferred or thefirst modified form of the invention.

In operation it is found that the invention set forth hereinbeforeinitiates the loom stopping impulse earlier than is possible with theusual protection and more time is therefore provided for dissipating theenergy of the moving parts of the loom. Induction units E! and E2 arespaced a substantial distance from the shuttle boxes adjacent to themand the length of time required for the shuttle to travel from theseunits to their respective boxes represents a gain in time which isavailable for stopping the loom beyond that now possible with the usualmechanical protection.

While the various parts of the electric circuits shown in Figs. 7 and 8are subject to some variation a few specific values found to besatisfactory Will be mentioned. The lay carried coils may generate from5 to 15 volts, condensers CI and C2 can be, respectively, 0.25 and 16microfarads, resistance RI may have a value of 1.57 megohms, while theresistance R2 can be one megohm. The resistance R3 is variable up toohms, while. the resistance R4 may be 10,000 ohms. The relay I2 may havea resistance of 3300 ohms and the resistance R5, which is a tube loadresistance, had a value of 4000 ohms. The secondary I0 supplied apotential of volts. The motor M operated with three phase alternatingcurrent and the unit MC of commercial form impressed direct current onthe motor to stop the loom. These values are illustrative of those whichhave been found satisfactory, but the invention is not limited to them.

From the foregoing it will be seen that the invention sets forthelectronically controlled loom protection mechanism includingcooperating parts on the lay and shuttle which generate an electricpotential at some point along the lay, and if desired under the warpshed, before the shuttle is boxed, and this potential is utilized tocontrol the grid of an electronic tube which is normally prevented fromfiring by the normal condition of the grid. The electric potential thusgenerated alters the grid so that the tube can fire and pass current forthe energization of an electromagnetic device. If this energizationoccurs during the period that switch 84 is open in the preferred form ofthe invent on, or just before lever arm I I rocks on a working stroke inthe modified form of the invention. the loom will cont nue to run. If,however. the shuttle is running slow the el ctric potential which itgenerates will come too late in the loom cvcle and the switch 84 of thepreferred form of the invention w ll be open simultaneously with switch13 and unit MC will stop the loom. In th first mod fied form of theinvention th se conditions result in an energization of solenoid I28 toolate to move the plunger I out of th path of lever arm H5 and as aresult the h draulic cylin er I23 and brake I24 will act to stop theloom. The invention is not limited to the particu r means for inducinelectric current by a flight of the shuttle, such as shown hereinbefore,since it will be sufficient if passage of the shuttle over a coil orunit on the lay will generate an electric impulse wh ch will change theelectric condition of the grid 63. The energy for creating the electricimpulse is d rived from the shuttle which in turn derives its energyfrom the picking mechanism. Furthermore, the invention is notnecessarily limited to the two units El and'E2, since a single unitlocated centrally along the length of the lay with appropriate earlyadiustment either of cams 80 or III) will suffice. The tim ng of theopening of switch 84 can be accom lished b any desired form ofadjustable switch. cam or the like. and the mechanism shown for instancein Fig. 2 for accomplishing this result is to be considered merely asillustrative. The invention further provides a lay with a unit in whichan electric impulse can be generated by the passage of the magnetizablebody on the shuttle.

Having thus described the invention it will be seen that changes andmodifications of the foregoing specific disclosure may be made withoutdeparting from the spirit and scope of the invention.

We claim:

1. In protection means for a loom having a shuttle which is pickedacross a lay, .an electric induction unit on the lay including a coil,,a body on the shuttle capable of inducing an electric potential in thecoil when the body passes the unit, electric circuit means including anelectromagnetic device and an electronic tube containing a gridelectrically connected to the coil and normally preventing firing of thetube, the shuttle when passing the induction unit generating an electricpotential in the coil which effects a change in the electric conditionof the grid to enable current to flow through the tube to energize theelectromagnetic device, and loom controlling means effective to stop theloom upon failure of the electromagnetic device to be energized at agiven time in the loom cycle due to 10 failure of the body on theshuttle to pass said unit at said given time.

2. In protection means for a loom having a shuttle which when runningproperly passes a given point along the lay at a given time in the loomcycle, electric induction means having a part on the lay at said givenpoint and having another part on the shuttle, said induction meanseffective to generate an electric potential when said other part on theshuttle passes said part on the lay, electric circuit means including anelectromagnetic device and an electronic tube having a control gridelectrically connected to said electric induction means and normallypreventing flow of electric current through the tube and electromagneticdevice, said grid having the electric condition thereof changed whensaid electric potential is generated to enable electric current to flowthrough the tube to energize said electromagnetic device, and loomcontrolling means effective to stop the loom upon failure of theelectromagnetic device to be energized at said given time in the loomcycle.

3. In protection means for a loom having a shuttle which when runningproperly passes a given point along the lay under the warp shed at agiven time in the loom cycle, electric induction means having a part onthe lay at said given point and having another part on the shuttleeffective to generate an electric potential when said other part on theshuttle moves in the warp shed and passes said part on the lay, electriccircuit means including an electromagnetic device and an electronic tubehaving a control grid electrically connected to said electric ind ctionmeans and normally preventing flow of electric current through the tubeand device, said grid having the electric condition thereof changed whensaid electric potential is generated to enable current to flow throughthe tube to energize said device, and loom controlling means effectiveto stop the loom upon failure of the device to be energized at saidgiven time in the loom cycle.

4. In protection means for a loom having a shuttle which is pickedacross a lay, an electric induction unit on the lay including a coilaround a permanent magnet, a body of metal on the shuttle capable ofinducting an electric potential in the coil when the shuttle passes saidunit, an electronic tube including a grid which normally is in suchelectric condition as to prevent flow of electric current through thetube normally tending to cause electric current to flow through the tubeand device and effective to energize the device when current can flowthrough said tube, electric connections between the coil and gridchanging the electric condition of the latter to enable current to flowthrough the tube when said electric potential is generated in said coil,and loom controlling means stopping the loom if the device fails to beenergized at a given time in the loom cycle.

5. In protection means for a loom having a shuttle which when runningproperly from one shuttle box to another shuttle box on the lay passes agiven point along the lay between the shuttle boxes at a given time inthe loom cycle,

electric induction. means partly on the lay atsaid given point andpartly on the shuttle generating an electric potential when the shuttlepasses said given point, an electromagnetic device, stopping meanseffective to stop the loom if the device fails to be energized at saidgiven time in the loom cycle, and electric means energizing said deviceat said time if said electric potential is 11 generated at said time inthe loom cycle, said electric means including an electronic tube thegrid of which has the electric condition thereof altered by saidgenerated electric potential.

6. In protecting means for a loom having a shuttle which travels overthe race plate of a lay, an electric induction unit supported by the layincluding a coil below the top of the race plate, a "-ferrous body onthe shuttle effective when passing the unit to generate an electricpotential therein, loom stopping means normally acting to stop the loomat a given time in the loom cycle, and electric controlling means forthe stopping means including an electromagnetic device and an-electronictube electrically connected to said coil and effective to prevent thestopping means from stopping the loom if said electric potential isgenerated by passage of said ferrous body over saidcoil: at said time inthe loom cycle.

'I. In protecting means for a loom having a shuttle which travels acrossa lay, a ferrous an electric potential when said ferrous bodypassesoverthe unit while the shuttle is moving across the lay, anormally deenergized electromagnetic device, loom controlling meansdependout upon energization of the device at a given time in the loomcycle to enable the loom to continue running, said controlling meansstopping theloom if the device fails to be energized at said given time,and electric means effective to energize said electromagnetic devicewhen said electric potential is generated in said coil, said body on theshuttle if passing the coil at saidtime in the loom cycle effectingenergization of the device by said electric means with resultantcontinued operation of the loom, and said electromagnetic deviceremaining deenergizedif said body fails to generate said electricpotential in the coil-at said time in the loom cycle with resultantstoppage of the loom by said controlling means.

8. In protector means fora loom having a lay provided with a shuttle boxat each end thereorand a'shuttle which is picked back and forth acrossthe lay from one boxto the other box, abocly of ferrous metal. on theshuttle, a unit on the lay including an electric coil located along'thelay at a point centrally of said boxes, said shuttle when passing overthe coil causing the generation in the latter of an electric potential,loom controlling means capable either of stopping'the loom at a giventime in the loom cycle or permitting continued loom operation, andelectric means controlling the loom controlling means dependent upongeneration of said electric potential and effective to cause the loomcontrolling means to stop the loom if said electric potential fails tobe generated at a given time in the loom cycle, said electric meansenabling the loom controlling means to permit continued running of theloom if said electric potential is generated at said given time.

9. In protection means for a loom having a shuttle which is pickedacross a lay, a member moving regularly during loom operation, re ularlyacting means moving in timed relation with said member normally tendingto stop the loom at a given point in the loom cycle, means to adjust thetime relation of the regularly acting means relatively to said member,an electromagnetic device effective when energized at said point in theloom cycle to prevent said regularly acting means from stopping theloom, co-

operating electric induction means partly on the shuttle and partly onthe lay including a coil on the lay effective to generate an electricpotential when the shuttle passes the coil, and electric circuit meansincluding the electromagnetic device and an electronic tube the grid ofwhich normally prevents electric current from flowing through the tubeto energize the electromagnetic device, said grid being electricallyconnected to the coil and being changed electrically to permit electriccurrent to pass through the tube to energize the electromagnetic devicewhen said electric potential is generated in the coil, the shuttle ifrunning on time causing generation of said electric potential at saidgiven point in the loom cycle, and the shuttle if running slow failingto cause generation of said electric potential with resultant failure ofenergization of the "electromagnetic device at said given point in theloomcycle, whereupon said regularly acting means effects loom stoppage.

18. In protection means fora loom having a shaft which rotatesduringloom operation in time with picking *mechanism which picks ashuttle across a lay, a cam on said shaft, an actuator lever rocked eachpick of the loom by said cam at a given time in the cycle of the loom,loom stopping means including an element normally in the path of saidactuator lever but movable relatively to said path and effective when insaid path and moved at said time by the actuator lever to stop the loom,an electromagnetic device effective when energized to move said elementout of the path of the actuator lever, an electric induction unit on thelay including a coil, a magnetizable body on the shuttle which whenpassing the coil generates an electric potential therein, electriccircuit means including the electromagnetic device and an electronictube efiective when electric current can pass through the tube toenergize the electromagnetic device, and a control grid in said tubeelectrically connected to the coil and normally preventing current frompassing through the tube but altered --electrically to enable current topass through the tube with resultant energization of the electromagneticdevice when said electric potential is generated in said coil, theshuttle if running on time effecting generation of said electricpotential and energization of the device to move said mem her out ofsaid path prior to rocking of the lever at ti in the loom cycle, theshuttle if running late failing .to efiect generation of said electricpotential at said time in the loom cycle, whereupon said element remainsin said path and is moved by said actuator lever to efifect loomstoppage.

11. In a lay for a loom having stopping means controlled by an electricimpulse, the laycomprising a beam, a race plate on the beam made ofmagnetizable material andformed with an opening therein, and an electricimpulse gen erating unit on the lay including a magnet in said openingspaced from the race plate and a coil wrapped around the magnet, saidunit effective to generate said electric impulse when a magnetizablebody passes the unit.

12. In a loom lay and shuttle for a loom having stopping meanscontrolled by an electric impulse, an electric impulse generating uniton the lay including a permanent magnet having two poles spaced alongthe length of the lay and a coil around the magnet, a magnetizable bodyon the shuttle having a length measured lengthwise 13 of the lay equalsubstantially to the center to center distance between said poles, saidbody when passing over the magnet generating said electric impulse insaid coil.

13. In protection means for a loom having a shuttle which is pickedacross a lay, an electric induction unit on the lay including a coil, abody on the shuttle capable of inducing an electric potential in thecoil when the body passes over the unit, a source of alternatingelectric current, an electronic power tube, an electromagnetic device,loom stopping means controlled by the device effective to stop the loomif the device fails to be energized by the time a given point is reachedin the loom cycle but ineffective to stop the loom if said device isenergized by said time, electric circuit means including said source,tube and device effective when electric current can pass through thetube to energize the device, a control grid in the tube normallypreventing current from passing through said tube, and electric meansincluding said coil and an electric condenser electrically connected tosaid grid and effective when said electric impulse is generated tocharge said condenser so that the side thereof connected to the gridshall be positively charged, said condenser being efiective after saidelectric impulse has been generated to maintain the grid in suchelectric condition as to permit electric current to flow through saidtube to energize said device.

14. In protection means fona loom having a lay with a shuttle box ateach end thereof and a shuttle which is picked across the lay fromeither shuttle box toward the other shuttle box, two

spaced electric impulse generating units on the lay between the shuttleboxes, each unit including a coil, a body of magnetizable material onthe shuttle effective when passing over said units to generate electricimpulses in said coils, electric loom controlling means including anelectronic tube having a control grid normally preventing electriccurrent from flowing through the tube, said loom controlling meansefiecting loom stoppage if the grid prevents flow of electric currentthrough the tube at a given point in the loom cycle, the shuttle whenpicked from either shuttle box and when running on time passing bothunits and generating an electric impulse in each coil and the impulse ofthe second coil to be passed by the shuttle being generated in time tochange the electric condition of said grid to enable current to flowthrough said tube at said given time.

15. In protection means for a loom having a shuttle which is pickedacross a lay, an electric induction unit on the lay including a coilaround a permanent magnet having poles spaced lengthwise of the lay, abody of metal on the shuttle of a length equal substantially to thecenter to center distance between said poles and capable of inducing anelectric potential in the coil when passing said unit, an electronictube including a grid which normally is in such electric condition as toprevent flow of electric current through the tube, an electromagneticdevice, electric circuit means normally tending to cause electriccurrent to flow through the tube and device and effective to energizethe device when current can flow through said tube, electric connectionsbetween the coil and grid changing the electric con, dition of thelatter to enable current to flow through the tube when said electricpotential is generated in said coil, and loom controlling means stoppingthe loom if the device fails to be ener-f gized at a given time in theloom cycle.

16. In protection means for a loom having a shuttle which when runningproperly passes a given point along the lay at a given time in the loomcycle, electric induction means having a part on the lay at said givenpoint and having another part of the shuttle efiective to generate anelectric impulse having positive and negative waves when said other partpasses the part on the lay, electric circuit means including anelectromagnetic device and an electronic tube having a control gridwhich normally prevents electric current from flowing through said tubeand device, electric connections between said part on the lay and saidgrid including a rectifier which allows the positive wave only of saidelectric impulse to be impressed on said grid, said grid having theelectric condition thereof altered when the positive wave of saidimpulse is impressed on the grid to enable current to flow through saidtube and energize said device, and loom controlling means effective tostop the loom upon failure of the device to be energized at said giventime in the loom cycle.

17. In protection means for a loom having a shuttle which when runningproperly in one direction passes a given point along the lay at a giventime in the loom cycle and when running properly in the oppositedirection passes a second given point along the lay at said given timein the loom cycle, two spaced electric induction units on the lay eachincluding a coil, one unit being located at said given point and theother unit being located-at said second point, means on the shuttleeffective to generate an electric impulse having positive and negativewaves in each coil as the shuttle travels along the lay either in saidone direction or in said opposite direction, electric circuit meansincluding an electromagnetic device and an electronic power tube havinga control grid which normally prevents electric current from flowingthrough the tube and device, electric connections between each coil andsaid grid electrically connecting said tric current to flow through saidtube and device to energize the latter, and loom controlling meanseffective to stop the loom upon failure of the device to be energized atsaid given time in the ,loom cycle.

18. In protection means for a loom having picking mechanism to propel ashuttle across a lay, loom controlling means tending to stop the loom ata given time in the loom cycle, electromagnetic means effective whenenergized at said given time to prevent said controlling means fromstopping the loom, electric circuit means including said electromagneticmeans and an electronic tube normally preventing electric current fromflowing through said circuit means and electromagnetic means buteffective when receiving an electric impulse to permit current to flowthrough the tube and circuit means to energize the electromagneticmeans, and electric impulse generating means having cooperating partsone of which is on the shuttle and the other of which is on the layeffective to generate said impulse by energy derived from the pickingmechanism when said .part on the shuttle passes said part on the lay.

19. In protecting means'for a loom having a shuttle picked back andforth across the lay and when running properly in one direction passes agiven point on the lay at a given time in the loom cycle and whenrunning properly in the opposite direction passes a second point alongthe lay at said given time, two spaced electric induction units on thelay each including a magnet and a coil, one unit being located saidgiven point'and the other unit being located at said second point, meanson the shuttle effec tive to generate an electric impulse havingpositive and negative waves in each coil as the shuttle travels alongthe lay, either in said one direction or in said opposite direction,electric circuit means including an electromag etic device and anelectronic power tube having a control grid which normally preventselectric current from flowing through the tube and device, electricconnections between each coil. and said grid electrically connectingsaid coils and including rectifier means which allows the positive waveonly of said electric impulses to be impressed on the grid and alsoprevent the impulse of each coil from passing through the other coilsaid grid having the electric condition thereof altered when thepositive waves of said impulses are impressed on the grid to permitelectric current to flow through said tube and device energize'thelatter, and loom controlling me elfective to stop the loom upon failureor the device to beenergized at said given time in the loom-cycle.

20. In electric protection means for a loom having a shuttle which whenrunning properly passes a given point along the lay at a given time inthe loom cycle, an electric relay, electric loom stopping meanscontrolled by the relay ef-- fective to stop the loom upon failure ofthe relay to be'energized for a period starting at said given time inthe loom cycle, electric circuit means including said relay, anelectronic tube having a'grid, and a condenser and resistance. saidcondenser and resistance connected so that the condenser can dischargethrough the resistance, and electric means actuated by the shuttle whenthe latter passes said given point to effect energization of saidcircuit means to alter the electric condition of the grid of the tubeand cause the tube to fire to energize the relay and also charge saidcondenser, and the condenser discharging through said resistance afterthe shuttle passes said given point and. the circuit means due todischarge of the condenser maintaining the grid in condition to causecontinued firing or" the tube during said period.

21. In electric protection means for a loom havinga shuttle which whenrunning properly passes a given point along the lay at a given time inthe loom cycle, an electric induction unit on the lay including a coil,a body on the shuttle capable of inducing an electric potential in thecoil when the body passes over said unit due to motion of the shuttlealong the lay, an electronic tube including a grid, an electromagneticdevice, loom stopping means controlled by the device eifective to stopthe loom if the device fails to be energized for a period starting atgiven time in the loom cycle butineliective to .stop the loom if thedevice is energized during said period, an electric condenser and aresistance connected so that the condenser can discharge through theresistance, and electric circuit means including theelectromagnetic'device, electronic tube and grid, condenser andresistance and said induction unit, said electric circuit meanseffective when the shuttle reaches said given point at said given timeto change the potential of the grid and cause the tube to fire andenergize the electromagnetic device and charge the condenser, thecondenser discharging through the resistance after the shuttle passessaid given point and said circuit means due to said discharge of thecondenser maintaining the potential of the grid changed to causecontinued firing of the tube.

22. In electric protection means for a loom having a shuttle which whenrunning properly passes a given point along the lay at :a given time inthe loom cycle, an electricrelay, electric loom stopping means effectiveto stop the loom if the relay fails to be energized for aperiod startingat said time in the loom cycle, an electric condenser, and electriccircuit means including said electric relay and condenser'and controlledby the shuttle and caused by the latter when the same passes said givenpoint to cause charging of the condenser and energization of said relay,the condenser discharging through said relay after the shuttle passessaid given point to keep the relay energized for said period.

23. In electric protection means for a m having a warp shed and means topick ashuttle through the warp shed, electronic means'for stopping theloom controlled by an electric impulse generated when the shuttle is inthe warp shed by cooperation of electric and magnetic elements one ofwhich is outside the warp shed intermediate the sides of the warpshedand the other of which is on the shuttle.

24. In electric protection means for a loom in which the path of flightof a shuttle passes through a warp shed, a normally open loomvcontrolling electric circuit which when closed at .a giveh time in theloom cycle efiects continued loom operation, electric means controllingsaid electric circuit located at a point along that part of the path offlight of the shuttle in the warp shed caused to effect closure of saidelectric circuit by the shuttle when the latter is in the warp shed andpasses said point, and means effective to stop the loom upon failure ofthe shuttle to reach said point by said given time in the cycle of theloom.

25. In protection means for a loom operating with warp threads which areseparated into different planes to define a warp shed through which ashuttle passes to lay weft in the warp shed when traveling across thelay, means creating a magnetic field extending across at least one ofsaid planes into the warp shed, a magnetizable body so located on theshuttle as to pass through said magnetic field. as the shuttle passesthrough the warp shed, and electric means operating incident to movementof said magnetizable body through said magnetic field controlling loomoperation and effecting loom stoppage upon failure of said magnetizablebody to pass through said magnetic field at a given time in the loomcycle.

26. In protection means for a loom operating with warp threads whichdefine a warp'shed, an element moving along a path' within the warp shedduring introduction of weft into the warp shed, a second element outsidethe warp'shed adjacent to said path, each element including magneticmaterial, one of said :elements having the magnetic condition thereofaltered when the first named element while in the warp shed REFERENCESCITED passes the second element during introduction of weft into thewarp shed, and electric circuit g g l fi are of record in the meanscontrolling loom operation and dependent upon said change in themagnetic field at a given 5 UNITED STATES PATENTS time in the cycle ofthe loom to efiect continued Number Name Date running of the loom.2,179,338 Lindegren Nov. '7, 1939 DONALD W. HOWE, JR. 2,482,943 SepavichSept. 27, 1949 VICTOR F. SEPAVICH.

